Molybdenum blue (MB), formed by partial reduction of Mo VI in an acidic aqueous solution, is a striking inorganic material due to its vivid blue color. It is a mixture of polyoxomolybdate (POM) clusters consisting of mixed-valent Mo V and Mo VI centers. [1][2][3] Although the initial exploration was made more than 200 years ago, [4] the first success in structural analysis of POM clusters was only reported in 1995, when Müller and coworkers isolated a crown-shaped POM cluster and obtained its crystal structure.[5] To date, they have also succeeded in structural determination of large POM clusters with hollow and spherical shapes. [6,7] Despite their interesting potentials in materials sciences, no examples have yet been reported of the utilization of such inorganic nano-objects for the fabrication of discrete inorganic/organic nanocomposite materials. Herein we report that the crown-shaped POM (molybdenum crown cluster; MC), upon mixing with metalloporphyrins having meso-aminophenyl substituents, forms discrete inclusion complexes, where the inorganic cavity of MC can accommodate up to three molecules of the guest compounds, to give spatially isolated metalloporphyrin molecules (Scheme 1). MC has a large cavity with a diameter of approximately 2.3 nm. [7] We expected that this cavity can incorporate proton acceptors through a hydrogen-bonding interaction, since a
Molybdenum blue (MB), formed by partial reduction of Mo VI in an acidic aqueous solution, is a striking inorganic material due to its vivid blue color. It is a mixture of polyoxomolybdate (POM) clusters consisting of mixed-valent Mo V and Mo VI centers. [1][2][3] Although the initial exploration was made more than 200 years ago, [4] the first success in structural analysis of POM clusters was only reported in 1995, when Müller and coworkers isolated a crown-shaped POM cluster and obtained its crystal structure.[5] To date, they have also succeeded in structural determination of large POM clusters with hollow and spherical shapes. [6,7] Despite their interesting potentials in materials sciences, no examples have yet been reported of the utilization of such inorganic nano-objects for the fabrication of discrete inorganic/organic nanocomposite materials. Herein we report that the crown-shaped POM (molybdenum crown cluster; MC), upon mixing with metalloporphyrins having meso-aminophenyl substituents, forms discrete inclusion complexes, where the inorganic cavity of MC can accommodate up to three molecules of the guest compounds, to give spatially isolated metalloporphyrin molecules (Scheme 1). MC has a large cavity with a diameter of approximately 2.3 nm. [7] We expected that this cavity can incorporate proton acceptors through a hydrogen-bonding interaction, since a
To extend the scaling beyond the most widely used poly(styrene-b-methyl methacrylate) (PS-b-PMMA), organic high- block copolymers (BCPs) were developed. Vertically oriented BCP domains were obtained by simple coat and bake process without application of an additional layer of a topcoat material. In addition, process-friendly conditions including low bake temperature (< 200 °C) and short bake time ( 5 min) provided a simple scheme to integrate these high- block copolymers to standard lithography process and pre-patterns defined by 193i lithography. Successful demonstration of directed self-assembly of these high- block copolymers on 193i-defined guiding pre-patterns offers a simple route to access well-aligned perpendicular lamellae and cylinders with a pitch less than 20 nm.
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